1. Technical Field of the Invention
The present invention relates to a refrigerant compressor which has a compression mechanism part and an electric motor part in a hermetic container.
2. Description of the Related Art
FIG. 8 shows a longitudinal sectional view of a conventional scroll compressor disclosed in Japanese Unexamined Patent Publication No. 2000-161254. In FIG. 8, a fixed scroll 1 and a guide frame 15 are shown. The peripheral part of the fixed scroll 1 is fixed to the guide frame 15 by bolts (not shown). From the side of the fixed scroll 1, a suction tube 10a is pressed penetrating a hermetic container 10.
A spiral blade 2b is provided on a seat 2a of an orbiting scroll 2. The form of the spiral blade 2b is substantially the same as a spiral blade 1b provided on a seat 1a of the fixed scroll 1. The spiral blade 1b and the spiral blade 2b geometrically form a compression chamber 1d. A boss part 2f being a hollow cylinder is provided at the central part of the surface of the seat 2a opposite to the surface where the spiral blade 2b exists. The boss part 2f is rotatably engaged with an orbiting shaft part 4b provided at the upper end of a main shaft 4. A thrust surface 2d is formed on the surface of the seat 2a opposite to the surface where the spiral blade 2b exists. The thrust surface 2d is slidably in contact with a thrust bearing 3a of a compliant frame 3.
The compliant frame 3 is supported in the radial direction at an upper surface 3d and a lower surface 3e provided on the external circumferential part of the compliant frame 3, by an upper surface 15a and a lower surface 15b provided on the internal circumferential part of the guide frame 15. A main bearing 3c and a sub-main bearing 3h at the center of the compliant frame 3 support the main shaft 4 rotated by a stator 7, in the radial direction. A connection passage 3s penetrating along the axial direction from the inside of the thrust bearing 3a is also provided. A thrust bearing side opening 2k is provided facing an orbiting scroll extraction hole 2j. 
Although an external circumferential surface 15g of the guide frame 15 is adhered to the hermetic container 10 by means of shrinkage fitting or welding, a passage is secured which leads refrigerant gas of high pressure discharged from a discharge port 1f of the fixed scroll 1 to a discharge tube 10b provided between the compression mechanism part and the electric motor element. This passage is formed by a concave part 15c provided at the outer peripheral part of the guide frame 15.
The orbiting shaft 4b at the upper end of the main shaft 4 is rotatably engaged with an orbiting bearing 2c of the orbiting scroll 2, and a main shaft balancer 4e is provided below the orbiting shaft 4b by shrinkage fitting. Furthermore, a main shaft part 4c which contacts the main bearing 3c and the sub-main bearing 3h of the compliant frame 3 during rotation is provided below the main shaft balancer 4e. Below the main shaft 4, a sub-shaft part 4d which is rotatably engaged with a sub-bearing 6a of a sub-frame 6 is formed. A rotor 8 is provided by shrinkage fitting between the sub-shaft part 4d and the main shaft part 4c. A first balancer 8a is fixed to the upper end surface of the rotor 8 and a second balancer 8b is fixed to the lower end surface of the rotor 8. Static balance and dynamic balance are retained by the three balancers: the first balancer 8a, the second balancer 8b, and the main shaft balancer 4e. An oil pipe 4f pressed in the lower end of the main shaft 4 sucks up refrigerating machine oil 10e collected in an oil reservoir 10g at the bottom of the hermetic container 10.
Now, the basic operation of this conventional scroll compressor will be explained. Sucked low-pressure refrigerant is led from the suction tube 10a into the compression chamber 1d formed by the spiral blades of the fixed scroll 1 and the orbiting scroll 2. The orbiting scroll 2 driven by the stator 7 decreases the capacity of the compression chamber 1d by an eccentric revolution movement. The sucked refrigerant becomes high pressure by this compression process, and is discharged into the hermetic container 10 from the discharge port 1f of the fixed scroll 1.
The refrigerating machine oil 10e collected in the oil reservoir 10g at the bottom of the hermetic container 10 is led by a difference of pressure to an orbiting bearing part 2g through a hollow space 4g penetrating, along the axial direction, the main shaft 4. The refrigerating machine oil which has become intermediate pressure by a throttle action of the orbiting bearing part 2g fills a space 2h (boss part space) surrounded by the orbiting scroll 2 and the compliant frame 3. Then, the refrigerating machine oil which has become intermediate pressure is led to a low pressure space via a pressure adjustment valve (not shown) connecting the space 2h and a low-pressure atmosphere space, and sucked into the compression chamber 1d with the refrigerant gas of low-pressure. By dint of this compression process, the refrigerating machine oil is discharged into the hermetic container 10 from the discharge port 1f with high-pressure refrigerant gas.
In the conventional scroll compressor of high-pressure shell type explained above, the refrigerant gas and the refrigerating machine oil are discharged in the state of being mixed as shown in FIG. 9. FIG. 9 illustrates flows of the refrigerant gas and the refrigerant according to the conventional compressor. In FIG. 9, the discharge port 1f, the concave part 15c provided at the outer peripheral part of the guide frame 15, and the discharge tube 10b are shown. The white arrow in FIG. 9 indicates a flow of the refrigerant gas, and the black arrow indicates a flow of the refrigerating machine oil.
The refrigerant gas and the refrigerating machine oil discharged from the discharge port 1f go through the concave part 15c in the state of mixed, go between the guide frame 15 and the electric motor element, and are finally discharged from the discharge tube 10b to the outside of the compressor. However, when they are discharged, rather much refrigerating machine oil is carried out of the compressor with the refrigerant gas. Therefore, there is a problem that pressure loss and deterioration of heat-conducting performance are performed in the unit and seizure of bearings in the compressor occurs because of oil lack, which decreases the reliability of the compressor.
One of objects of the present invention is to solve the above-mentioned problem in order to obtain a compressor of high reliability. It is another object to obtain a compressor in which the refrigerant gas and the refrigerating machine oil can be separated. Moreover, the present invention aims at obtaining a compressor in which the separated refrigerating machine oil can be returned to the oil reservoir and the mount of refrigerating machine oil carried outside of the compressor can be suppressed.
According to one aspect of the compressor of the present invention, the compressor includes:
a compression mechanism part, included in a hermetic container, for compressing refrigerant sucked from the outside of the hermetic container and discharging compressed refrigerant to a discharge space in the hermetic container;
an electric motor part composed of a stator and a rotor, facing a first space which is at the opposite side, along the axial direction, of the discharge space with respect to the compression mechanism part in the hermetic container, for driving the compression mechanism part through a main shaft;
a discharge tube provided in the hermetic container, being open to the first space;
a passage at the external circumferential side of the compression mechanism part, for connecting the discharge space with the first space; and
a fan provided at the end of the rotor, facing the first space,
wherein the refrigerant discharged into the discharge space passes through the passage at the external circumferential side of the compression mechanism part to reach the first space, and passes the fan to be discharged to the outside of the hermetic container.
According to another aspect, the compressor of the present invention further includes:
a passage at the external circumferential side of an electric motor, provided at the external circumferential side of the stator, for connecting the first space and the second space which is at the opposite side, along the axial direction, of the first space with respect to the electric motor part; and
a passage at the internal circumferential side of the electric motor, provided at between the stator or the rotor and in the rotor, for connecting the first space and the second space,
wherein the fan sucks the refrigerant from the internal circumferential side of the fan and discharges the refrigerant to the external circumferential side of the fan, and wherein the refrigerant passes in order of the passage at the external circumferential side of the electric motor, the passage at the internal circumferential side of the electric motor, and the fan, and is discharged to the outside of the hermetic container.
According to another aspect of the compressor of the present invention, the passage at the internal circumferential side of the electric motor is formed as at least one penetration hole, penetrating along the axial direction, provided at the rotor.
According to another aspect of the compressor of the present invention, the passage at the external circumferential side of the electric motor is formed as a notch or a concave part provided at the external circumferential side of the stator.
According to another aspect of the compressor of the present invention, the rotor includes a plate for oil separation at the end of the rotor, facing the second space.
According to another aspect of the compressor of the present invention, the plate includes at least one penetration hole.
According to another aspect of the compressor of the present invention, the plate is fixed by a caulker with a second balancer provided at the end of the rotor, facing the second space.
According to another aspect of the compressor of the present invention, a surface of the fan and an upper surface of a first balancer provided at the end of the rotor, are located on one plane.
According to another aspect of the compressor of the present invention, the fan is fixed by a caulker with the first balancer provided at the end of the rotor, facing the first space.
According to another aspect of the compressor of the present invention, the passage at the external circumferential side of the compression mechanism part is located at the position away from the discharge tube by 90 degrees or greater than 90 degrees of a phase angle along the direction of the circumference.
The above-mentioned and other objects, features, and advantages of the present invention will be made more apparent by reference to the following detailed description when taken in conjunction with the accompanying drawings.